Location of SBI
Based on the evaluation of SBI location, a high number of lesions were localized in the right hemisphere. We speculated the possible causes of SBI in the right hemisphere, which were as follows: First, MICS is performed while the patients are in the left lateral decubitus position at our institution, and this might have made it easier for debris and air to reach the right-dominant vasculature area. Floyed et al. reported a similar tendency on MRI after median sternotomy 6. In the reports of Knipp et al. 11 and Barbut16, the percentage of embolic lesions in the posterior cerebral circulation was high. However, the actual cause of lesion localization in these studies was not identified. Second, the brachiocephalic artery, which is the first artery from the heart other than the coronary artery, is the final point of blood flow in retrograde perfusion. Therefore, air and debris in the heart are most likely to burst out during the time at which cardiac beating begins after the release of the aortic clamp, and the brachiocephalic artery becomes the boundary between retrograde perfusion and cardiac output. Then, the air and debris can flow to the brachiocephalic artery.